Network Working Group C. Schmoll
Request for Comments: 5471 Fraunhofer FOKUS
Category: Informational P. Aitken
B. Claise
Cisco Systems, Inc.
March 2009
Guidelines for IP Flow Information Export (IPFIX) Testing
Status of This Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
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Schmoll, et al. Informational [Page 1]

RFC 5471 Guidelines for IPFIX Testing March 20091. Introduction
An IPFIX implementation, whether in software, firmware, or hardware,
needs to be tested thoroughly in order to check its robustness and
gain confidence in the conformity to the IPFIX documents on which it
is based.
For a testable IPFIX software tool kit, one needs at least one IPFIX
Exporting Process and one IPFIX Collecting Process. However, when
one has, for example, only implemented a Collector, then it can be
complemented with a third-party Exporter for these tests.
This document specifies guidelines for a series of tests that can be
run on the IPFIX Exporting Process and Collecting Process in order to
probe the conformity and robustness of the IPFIX protocol
implementations.
The tests listed here can form a valuable common basis for
implementers involved in interoperability testing when all of them
use these tests to check their own Exporting Process and Collecting
Process implementation first.
The tests can be executed in a testbed environment or on a live
network.
However, care should be taken regarding the "stress/load test" and
the "temporary network disconnect", as they might impact other
systems in the network. We recommend that these specific tests
should be executed only in a testbed environment.
1.1. Document Scope
This document lists tests intended to be performed between an
implementation of an IPFIX Exporting Process and an IPFIX Collecting
Process. For some tests, multiple instances of each of those
components (Observation Points, Metering Process, Exporting Process,
Collecting Process) are involved. The testing of those different
IPFIX components complicates the testing as usually one tests his
software against an existing implementation, which is proven to be
compliant. In some cases, two unproven implementations of the
Exporting Process and Collecting Process must be tested against each
other. The tests range from basic transport connectivity to export
of Template and associated Data Records, high load on the Collecting
Process, and error condition situations. This document is not
intended as a replacement for formal testing software procedures
based on, e.g., TTCN3 (http://www.ttcn-3.org/) but as a best-
practices approach to an informal testing of a developer's IPFIX
implementation.
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RFC 5471 Guidelines for IPFIX Testing March 20091.2. IPFIX Documents Overview
The IPFIX protocol [RFC5101] provides network administrators with
access to IP Flow information. The architecture for the export of
measured IP Flow information out of an IPFIX Exporting Process to a
Collecting Process is defined in [RFC5470], per the requirements
specified in [RFC3917].
[RFC5470] specifies how IPFIX Data Records and Templates are carried
via a congestion-aware transport protocol from IPFIX Exporting
Processes to IPFIX Collecting Processes. IPFIX has a formal
description of IPFIX Information Elements, their name, type, and
additional semantic information, as specified in [RFC5102]. Finally,
[RFC5472] describes what type of applications can use the IPFIX
protocol and how they can use the information provided. It
furthermore shows how the IPFIX framework relates to other
architectures and frameworks.
2. Terminology
IPFIX-specific terminology used in this document is defined in
Section 2 of [RFC5101]. In this document, as in [RFC5101], the first
letter of each IPFIX-specific term is capitalized.
2.1. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
3. Test Specifications
The tests described in this section MAY be performed using an IPFIX
Exporting Process on one host and an IPFIX Collecting Process on a
different host. The configuration of the Observation Point, Metering
Process, Exporting Process, and Collection Process SHOULD be recorded
for every test along with the test results.
The successful execution of all tests described in this section will
give the tester a high confidence that the tested implementation is
conformant with the IPFIX architecture and protocol. It does however
not provide a 100% comprehensive coverage or formal proof of
conformance.
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RFC 5471 Guidelines for IPFIX Testing March 20093.1. Exporting Process/Collecting Process Connectivity Tests
This section lists the basic tests that are preconditions for the
more complex tests specified in later sections of this document.
3.1.1. Connectivity Tests between the Exporting Process and Collecting Process
The tester must create one Exporting Process and one Collecting
Process, must configure the Exporting Process to export at least one
Template Set and associated Data Records to the Collecting Process,
and must cause the Exporting Process to initiate the export.
When the Exporting Process and Collecting Process are to be connected
by a Stream Control Transmission Protocol (SCTP) transport, the
tester must ensure that an SCTP association is established.
When the Exporting Process and Collecting Process are to be connected
by a TCP transport, the tester must ensure that a TCP connection is
established.
The tester must ensure that the Transport Session parameters (IP
addresses and ports) are correct.
Note that specifying instructions and tools on how to ensure that a
Transport Session is correctly established and that the parameters
are correct is out of the scope of this document.
The tester must ensure that the Data Records are actually exported.
The transmitted data might be observed online with an appropriate
packet sniffing tool. Such a tool is also a viable help to check if
the initial connection (SCTP, TCP) has been successfully established.
The tester must record which combinations of IPv4 and IPv6
transports, and UDP, SCTP, and TCP transmission protocols are
supported, and should perform the test for all the supported
combinations.
3.2. Template and Data Record Tests
This section lists tests for checking the correct transmission of
IPFIX Template Sets and associated Data Sets.
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RFC 5471 Guidelines for IPFIX Testing March 20093.2.1. Transmission of Template with Fixed-Size Information Elements
The tester must create a Template with a few fixed-size Information
Elements where each data type specified in Section 6.1 of [RFC5101]
(octet, unsigned16, unsigned32 ...) is used at least once, and cause
the Template and associated Data Records to be exported over all
applicable combinations of transports and protocols in Section 3.1.
The tester must ensure that the Template and associated Data Records
were correctly received and decoded by the Collecting Process. For
this process, the use of verbose debugging output is suggested in
order to allow a detailed comparison with the sent (and therefore
expected) data.
3.2.2. Transmission of Template with Variable-Length Information Elements
The tester must create a Template with a mixture of fixed-sized and
variable-length Information Elements, as specified in Section 7 of
[RFC5101], and cause the Template and associated Data Records to be
exported over all applicable combinations of transports and protocols
in Section 3.1.
The tester must ensure that the Template contains at least:
o a single variable-length Information Element.
o a single variable-length Information Element followed by a
fixed-length Information Element.
o a fixed-length Information Element followed by a variable-
length Information Element.
o multiple variable-length Information Elements.
The tester must ensure that the Template and associated Data Records
were correctly received and decoded by the Collecting Process.
3.2.3. Set PaddingSection 3.3.1 of [RFC5101] specifies IPFIX Set alignment using
padding.
The tester must configure a packet generator to generate two Data
Sets with padding in between consisting of zero valued octets, as
shown in Figure 1. They must be exported to the Collecting Process,
which must correctly decode the Data Sets and all the Data Records.
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RFC 5471 Guidelines for IPFIX Testing March 2009
+--------------------------------------------------+
| Set Header #1 |
+--------------------------------------------------+
| Data Record |
+--------------------------------------------------+
| Data Record |
+--------------------------------------------------+
...
+--------------------------------------------------+
| Data Record |
+--------------------------------------------------+
| Padding with 0 valued octets |
+--------------------------------------------------+
| Set Header #2 |
+--------------------------------------------------+
| Data Record |
+--------------------------------------------------+
Figure 1
3.2.4. Record Padding
The tester must configure a packet generator to generate a Template
that contains the padding Information Element (i.e., paddingOctets).
The Template and associated Data Records must be exported to the
Collecting Process, over all applicable combinations of transports
and protocols in Section 3.1.
The tester must repeat the test with various padding sizes, including
padding to boundaries other than 4 or 8 octets.
The tester must ensure the Collecting Process correctly interprets
cases where the Data Records are so short that the padding is equal
to or longer than the length of the record, so the padding might
otherwise be interpreted as another record (e.g., 1 byte TOS plus 3
bytes of padding). Refer to the specifications in Section 3.3.1 of
[RFC5101]. Figure 2 depicts such a Template, while Figure 3 depicts
a Data Record conforming to that Template.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The tester must ensure that the Template Withdrawal Message was
correctly received and decoded by the Collecting Process, and that
the previously sent Template was discarded by the Collecting Process.
3.2.5.2. Withdrawal of a Previously Withdrawn Template
The tester must create, export, and withdraw an IPFIX Template as
described in Section 3.2.5.1.
The tester must cause the Exporting Process to send a second IPFIX
Template Withdrawal Message to the Collector in respect of the same
Template. The Template Withdrawal Message must be sent over the same
Transport Session as the Template.
The tester must ensure that the Collecting Process discards the IPFIX
Message and shuts down the SCTP association or closes the TCP
connection. The tester must check that the Collecting Process logged
the error.
3.2.5.3. Withdrawal of a Previously Unsent Template
The tester must cause the Exporting Process to send an IPFIX Template
Withdrawal Message to the Collector in respect of a Template that has
not yet been exported. The Template Withdrawal Message must be sent
over a reliable transport.
The tester must ensure that the Collecting Process discards the IPFIX
Message and shuts down the SCTP association or closes the TCP
connection. The tester must check that the Collecting Process logged
the error.
3.2.5.4. Withdrawing All Data Templates
The tester must create several IPFIX Templates and cause them to be
exported to an IPFIX Collector over a reliable transport.
The tester must ensure that the Templates were correctly received and
decoded by the Collecting Process.
The tester must cause the Exporting Process to send an IPFIX All Data
Templates Withdrawal Message to the Collector over the same Transport
Session as the Templates.
The tester must ensure that the All Data Templates Withdrawal Message
was correctly received and decoded by the Collecting Process, and
that all the previously sent Templates were discarded by the
Collecting Process.
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RFC 5471 Guidelines for IPFIX Testing March 20093.2.5.5. Withdrawing All Option Templates
The tester must create several IPFIX Option Templates and cause them
to be exported to an IPFIX Collector over a reliable transport.
The tester must ensure that the Option Templates were correctly
received and decoded by the Collecting Process.
The tester must cause the Exporting Process to send an IPFIX All
Option Templates Withdrawal Message to the Collector over the same
Transport Session as the Templates.
The tester must ensure that the All Option Templates Withdrawal
Message was correctly received and decoded by the Collecting Process,
and that all the previously sent Option Templates were discarded by
the Collecting Process.
3.3. Information Element Tests
This section lists the tests that cover the use of Information
Elements.
3.3.1. Enterprise-Specific Information Elements
The tester must cause the export of a Template and associated Data
Record that makes use of Enterprise-specific Information Elements as
specified in Section 3.2 of [RFC5101].
The tester must ensure that the Template and associated Data Record
are correctly received and decoded by the Collecting Process, and it
must ensure that Information Elements that are unknown to the
Collecting Process are not silently discarded.
3.3.2. Reduced Size Encoding of Information Elements
The tester must cause the export of a Template and associated Data
Record containing Information Elements using reduced size encoding as
specified in Section 6.2 of [RFC5101].
The tester must ensure that in the case of Information Elements
transmitted using reduced size encoding, the Collecting Process is
aware of the real size of each Information Element and not only the
reduced size used for its transmission.
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RFC 5471 Guidelines for IPFIX Testing March 20093.3.3. Multiple Instances of the Same Information Element in One Template
The tester must cause the export of a Template and associated Data
Record containing multiple instances of the same Information Element
consecutively.
The tester must ensure that the Collecting Process is able to parse
the IPFIX Message, and that it stores all values received for all the
Information Elements that appeared multiple times in the Template
definition.
The tester must ensure that the Collecting Process reports the
Information Elements in the same order as they were specified in the
Template Record, as specified in Section 8 of [RFC5101].
The tester must cause the export of another Template and associated
Data Record containing multiple instances of the same Information
Element with other Information Elements in between.
The tester must ensure that the Collecting Process is able to parse
the IPFIX Message, and that it stores all values received for all the
Information Elements that appeared multiple times in the Template
definition.
The tester must ensure that the Collecting Process reports the
Information Elements in the same order as they were specified in the
Template Record, as specified in Section 8 of [RFC5101].
3.4. Options Template Tests
This section lists the tests that cover the correct transfer of IPFIX
Options Templates.
3.4.1. Using Any Information Elements as Scope
Options Templates contain scope fields that give the context of the
reported Information Elements in the corresponding Data Records.
Scope fields are an Information Element specified in [RFC5102].
The tester SHOULD perform the export of Options Template Records
containing various different Information Elements of each of the
abstract data types specified in Section 6.1 of [RFC5101] (octet,
unsigned16, unsigned32 ...) in their scope fields, and must export a
Data Record using each Template.
The tester must check that the Templates and the associated Data
Records are correctly received and decoded by the Collecting Process.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The tester must ensure that the Collecting Process accepts
Information Elements in the scope field other than IPFIX Information
Elements that have been recorded by IANA.
The tester must ensure that the Collecting Process accepts an
Enterprise-specific Information Element in the scope field.
As specified in Section 3.4.2.1 of [RFC5101], the Scope Field Count
must NOT be zero. The tester must cause the export of an Options
Template Record containing a Scope Field Count of zero.
The tester must ensure that the Collecting Process shuts down the
SCTP association and discards the IPFIX Message. The tester should
check that the Collecting Process logged the error.
3.4.2. Using Multiple Scopes
The tester must cause the export of an Options Template Record
containing multiple scope fields, and a Data Record conforming to
that Template.
The tester must ensure that the Collecting Process reports the
Information Elements in the same order as they were specified in the
Options Template Record, as specified in Section 3.4.2.1 of
[RFC5101].
3.4.3. Metering Process Statistics Option Template
The tester must create a Metering Process Statistics Option Template,
as specified in Section 4.1 of [RFC5101], and cause the Option
Template and an associated Data Record to be exported.
The tester must ensure that the Collecting Process correctly receives
and decodes the Option Template and associated Data Record.
The tester must also check that the optional meteringProcessId Scope
Field is supported by the Collecting Process implementation.
If several Metering Processes are available on the Exporter
Observation Domain, the tester must create a Metering Process
Statistics Option Template containing multiple scopes and an
associated Data Record, must cause the Option Template and associated
Data Record to be exported, and must ensure that the Collecting
Process correctly receives and decodes the Option Template and
associated Data Record.
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RFC 5471 Guidelines for IPFIX Testing March 20093.4.4. Metering Process Reliability Statistics Option Template
The tester must create a Metering Process Reliability Statistics
Option Template, as specified in Section 4.2 of [RFC5101], and must
cause the Option Template and an associated Data Record to be
exported.
The tester must ensure that the Collecting Process correctly receives
and decodes the Option Template and associated Data Record.
The tester must also check that the optional meteringProcessId Scope
Field is supported by the Collecting Process implementation.
3.4.5. Exporting Process Reliability Statistics Option Template
The tester must create an Exporting Process Reliability Statistics
Option Template, as specified in Section 4.3 of [RFC5101], and must
cause the Option Template and an associated Data Record to be
exported.
The tester must ensure that the Collecting Process correctly receives
and decodes the Option Template and associated Data Record.
3.4.6. Flow Keys Option Template
The tester must create a Flow Keys Option Template, as specified in
Section 4.4 of [RFC5101], where the templateId refers to an existing
Template, and must cause the Option Template and an associated Data
Record to be exported.
The tester must ensure that the Collecting Process correctly receives
and decodes the Option Template and associated Data Record, and it
must ensure that the Collecting Process associates the Flow Keys with
the right Data Record Information Elements.
The tester must create another Flow Keys Data Record to be exported
where the associated templateId has insufficient fields to satisfy
the flowKeyIndicator.
The tester must ensure that the Collecting Process discards the IPFIX
Message and shuts down the SCTP association or closes the TCP
connection. The tester must check that the Collecting Process logged
the error.
The tester must create another Flow Keys Option Template, where the
templateId refers to a non-existing Template, and must cause the
Option Template and an associated Data Record to be exported.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The tester must ensure that the Collecting Process shuts down the
SCTP association and discards the IPFIX Message. The tester should
check that the Collecting Process logged the error.
3.5. Stress/Load Tests
Stress tests are used to check correct behavior and robustness of an
IPFIX Collecting Process implementation when a number of Data Records
arrive very quickly. This is especially important when IPFIX over
UDP is used, since in that case a slow Collecting Process cannot
block the IPFIX Exporting Processes from exporting because UDP is not
congestion aware.
The tests may be dependent upon the hardware and transport technology
in use. Therefore, the tests may need to be scaled up or down to
meet the needs of the particular implementation. However, the
implementer must ensure that the implementation is stable under
excessive traffic conditions, for whatever definition of "excessive"
applies at their intended installation.
The implementer must ensure the correct operation of the Exporting
Process and/or Collecting Process when the Collecting Process is
incapable of processing records at the rate that they are received.
3.5.1. Large Number of Records for One Template
The tester should export many Data Records to the Collecting Process,
all conforming to the same Template, in order to put the Collecting
Process under stress.
Depending on what the Collecting Process does (save to file, store to
database, analyze the data) the Collecting Process may use up a lot
of memory.
The tester must ensure that, if the Collecting Process runs out of
memory, it shuts down the specific SCTP association or closes the TCP
connection but remains available to receive data on other open
Transport Sessions and also stays available for future Transport
Sessions.
3.5.2. Excessive Rate of Incoming Data Records
The tester should perform a test where Data Records are exported to
the Collecting Process with an increasing export rate.
For TCP or SCTP in reliable mode, the tester must ensure that the
export stalls the Exporting Process once the Collecting Process
becomes fully loaded.
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RFC 5471 Guidelines for IPFIX Testing March 2009
For UDP export, the tester must ensure that the Collecting Process
drops records as it becomes overloaded, and must check that the
Collecting Process logged a warning.
3.5.3. Large Templates
The tester must create Templates with the maximum possible number of
Information Elements and cause these to be exported to the Collecting
Process.
The total length field in the IP header is 16 bits, allowing a length
up to 65535 octets in one application-level datagram. This limits
the number of Information Elements one can specify in an IPFIX
Template when using UDP export. SCTP and TCP are streaming
protocols, so they do not impose much restriction on the packet
level. UDP requires 20 octets for a minimal IPv4 header, 8 octets
for the UDP header, 16 octets for the IPFIX header, 4 octets for the
Set header, and 4 octets for the Template header, so the Template
definition may be up to (65535 - 20 - 8 - 16 - 4 - 4) = 65483 octets
long. The minimum IPFIX Information Element specification requires 4
octets: two for the Information Element ID and two for the field
length. Therefore, the maximum number of IPFIX Information Elements
in a single Template is 65483 / 4 = 16370. With this many
Information Elements, the Template will be 65480 octets long, while
the entire packet will be 65532 octets long.
The tester must create Data Records conforming to this Template, and
cause them to be exported. Note that, for the implementation, the
associated Data Records might be smaller or larger than the Template
Records depending on the length of the Information Elements defined
by the Template and on the presence of variable-length Information
Elements.
The tester must ensure that the Collecting Process correctly receives
and decodes the Template and associated Data Records.
3.5.4. Many New Templates within the Data Template Timeout Interval
The tester should create a large number of different Templates and
cause them to be exported to the Collecting Process to stress test
the Collecting Process's memory consumption.
The tester must ensure that the Collecting Process gracefully
discards Templates if it's running out of memory resources, and it
should check that warnings are logged.
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RFC 5471 Guidelines for IPFIX Testing March 20093.5.5. Multiple Exporting Processes Exporting to One Collecting Process
The tester must configure multiple Exporting Processes to export
Templates and associated Data Records to the same Collecting Process
at the same time.
The tester must ensure that all the Templates and associated Data
Records are correctly received and decoded at the Collecting Process,
and that no Exporting Process stalls or disconnects completely unless
the Collecting Process runs out of memory.
3.5.6. Export from One Exporting Process to Multiple Collecting Processes
If the Exporting Process supports multiple simultaneous export
destinations, the tester must configure the Exporting Process to
export Data Records in parallel to different Collecting Processes.
The tester must configure the use of a mixture of simple and complex
Templates and ensure they are all correctly received and decoded by
all the Collecting Processes.
3.6. Error Handling
This section lists and describes a number of problems that might
occur in either the network or data transmission or related to wrong
information encoding, and that the IPFIX Exporting Process and
Collecting Process must be capable of handling in a graceful way. It
is intended to test the robustness and fault tolerance of the IPFIX
Processes.
3.6.1. Temporary Network Disconnect
The IPFIX Exporting Process and Collecting Process behavior must be
checked upon interruptions of data transmission due to network
failures (whether physical or logical, e.g., defective routing).
The tester must configure continuous export over all applicable
combinations of transports and protocols in Section 3.1, in turn.
For SCTP-based associations and TCP-based connections, the tester
should create a short disconnect between the Exporting Process and
the Collecting Process (e.g., by momentarily interrupting the network
connection) and must ensure that export continues after the
connection is repaired. The tester must then create a longer
disconnection between the Exporting Process and Collecting Process,
and it must ensure that export continues after the connection is
repaired.
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RFC 5471 Guidelines for IPFIX Testing March 2009
For UDP-based data export, there is no noticeable connection loss,
but data received with non-consecutive sequence numbers indicates
data loss. Refer to the sequence number specifications in Section3.1 of [RFC5101]. The tester should create a short disconnect
between the Exporting Process and Collecting Process, and it must
ensure that this is recognized and reported by the Collecting Process
per Section 3.1 of [RFC5101].
3.6.2. Exporting Process Termination and Restart during Data Transmission
An IPFIX Collecting Process might be confronted with a faulty
Exporting Process implementation that suddenly crashes, dropping any
open connections. The Exporting Process may be restarted again soon
after the crash.
Such an event will only be visible to the Collecting Process when the
IPFIX Messages (Templates and associated Data Records) are carried
over TCP or SCTP. For export via UDP, no such test is available due
to the connection-less nature of the transport.
The tester must configure continuous export over all applicable
combinations of SCTP and TCP transports and protocols in Section 3.1,
in turn. For each combination, the tester must establish export,
then kill the active Exporting Process.
The tester must ensure that the associated Collecting Process shuts
down SCTP associations and closes TCP connections associated with
that export after a suitable timeout period.
The tester must Ensure that the Collecting Process discards the
Template(s) received on the killed transport session.
The tester must restart the Exporting Process again, and it must
ensure that the Exporting Process exports the Templates again.
The tester must ensure that the Collecting Process receives and
accepts both Templates and associated Data Records from the new
Exporting Process running at the same source host.
3.6.3. Collecting Process Termination and Restart during Data Transmission
An IPFIX Exporting Process might be confronted with a faulty
Collecting Process implementation that suddenly crashes, dropping any
open Transport Sessions. The Collecting Process may be restarted
again soon after the crash.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The tester must set up an Exporting Process and Collecting Process
and cause IPFIX Templates and associated Data Records to be exported
over all applicable combinations of SCTP and TCP transports and
protocols in Section 3.1, in turn. Via UDP, the restart of the
Collecting Process will be invisible to the Exporting Process and
have no effect.
The tester must terminate the Collecting Process while the export is
in progress, and must ensure that the Exporting Process shuts down
SCTP associations and closes TCP connections associated with that
Collecting Process.
The tester must restart the Collecting Process and ensure that the
Exporting Process connects to the Collecting Process again and that
it exports the IPFIX Templates again.
The tester must ensure that the new Collecting Process correctly
receives and decodes the IPFIX Data Records again.
3.6.4. Incorrect Template Records and Options Template Records
These tests verify the Collecting Process's operation when it
receives a Template Record or Options Template Record with an invalid
message length. Refer to the specifications in Section 3.4.1 and
3.4.2 of [RFC5101], respectively.
Consider the example Template Record shown in Figure 4. This
Template record is missing one Information Element ID and one
Information Element length field. There is insufficient data in the
Set for the specified Set length, and the overall record is four
octets too short for the specified total length.
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RFC 5471 Guidelines for IPFIX Testing March 2009
(b) Consider the IPFIX Template shown in Figure 4, modified with
total length = 28. In this case, the IPFIX Message has to be
rejected because the field count = 2 and there is no second
Information Element record present in the Set. The available
data is exhausted after reading the first Information Element
record.
The tester must create the modified Template and cause the
Exporting Process to export it. The tester must ensure that the
Collecting Process's behavior is as specified above for each
transport type.
(c) Consider the IPFIX Template shown in Figure 4, modified with
total length = 26. In this case, the IPFIX Message has to be
rejected because the IPFIX Message length is too short. After
the first Information Element, the IPFIX Message data is
exhausted according to the total length information.
The tester must create the modified Template and cause the
Exporting Process to export it. The tester must ensure that the
Collecting Process's behavior is as specified above for each
transport type. The TCP connection used for this test must be
manually reset after the test.
(d) Consider the IPFIX Template shown in Figure 4, modified with
field count = 1. In this case, the IPFIX Message must be
rejected because the total length is too large and does not match
the amount of data available.
The tester must create the modified Template and cause the
Exporting Process to export it. The tester must ensure that the
Collecting Process's behavior is as specified above for each
transport type. This test is not applicable for TCP transport.
(e) Finally, when the IPFIX Template shown in Figure 4 is extended
with the data shown in Figure 5, it becomes a correct IPFIX
Template.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| Info Element Identifier = 12| Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5
The tester must create the modified Template and cause the
Exporting Process to export it. The tester must ensure that the
Template is accepted by the Collecting Process for each transport
type.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The example Template record shown in Figure 6 must be dropped because
the scope field count = 0.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version = 10 | Total Length = 30 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Export Time = 1155202151 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number = 0x12345678 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Observation Domain ID = 0x33334444 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Set Length = 14 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 257 | Field Count = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 0 |0| Info Element Identifier = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6
The tester must create the Template shown in Figure 6 and cause the
Exporting Process to export it. The tester must ensure that the
IPFIX Message is discarded by the Collecting Process for each
transport type, and must check that the Collecting Process logs an
error. The tester must ensure that the Collecting Process also shuts
down the SCTP association or closes the TCP connection.
The tester must create an IPFIX Options Template where the field
count is less than the scope field count, and cause the Exporting
Process to export it. Use the above IPFIX Options Template with
scope field count = 2. The tester must ensure that the Template is
discarded by the Collecting Process for each transport type, and must
check that the Collecting Process logs an error. The tester must
ensure that the Collecting Process shuts down the SCTP association or
closes the TCP connection.
3.6.5. Incorrect Data Record
The tester must create the following invalid Data Records and cause
them to be exported to the Collecting Process over all applicable
combinations of transports and protocols in Section 3.1.
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RFC 5471 Guidelines for IPFIX Testing March 2009
o IPFIX Message too short.
o Illegal use of reduced size encoding.
o Invalid length specification in case of variable-length
Information Elements.
The tester must ensure that the Collecting Process discards the IPFIX
Message and shuts down the SCTP association or closes the TCP
connection.
3.6.6. Export of Non-Matching Template and Data Records
The tester must create Templates and associated Data Records that
fail to conform to those Templates in the following ways:
o too few Information Elements in Data Record
o too many Information Elements in Data Record
The tester must cause the Templates and associated Data Records to be
exported to the Collecting Process over all applicable combinations
of transports and protocols in Section 3.1.
The tester must ensure that the Collecting Process discards the IPFIX
Message and shuts down the SCTP association or closes the TCP
connection.
3.6.7. Unknown Set IDs
The tester must create Template Sets, Option Template Sets, and
associated Data Sets using Set IDs which are unknown to the
Collecting Process, and cause these to be exported to the Collecting
Process over all applicable combinations of transports and protocols
in Section 3.1.
Per Section 3.3.2 of [RFC5101], only the Set ID values 2 and 3 denote
valid Sets.
The tester must ensure that the Collecting Process ignores the
unknown Sets, logs a warning, and processes the remainder of the
IPFIX Message.
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RFC 5471 Guidelines for IPFIX Testing March 20093.6.8. Re-Using Template IDs3.6.8.1. Using SCTP Transport
Refer to Section 9 of [RFC5101] for the Collecting Process's SCTP
Template management specifications.
The tester must create an IPFIX Template and cause it to be exported
to a Collecting Process over SCTP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must cause the same Template to be exported to the same
Collecting Process over the same SCTP association, and must ensure
that the Collecting Process resets the SCTP association and discards
the IPFIX Message.
The tester must create another IPFIX template and cause it to be
exported to the Collecting Process over SCTP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must modify the Template contents while retaining the same
Template ID.
The tester must cause the modified Template to be exported to the
same Collecting Process over the SCTP same association, and must
ensure that the Collecting Process resets the SCTP association and
discards the IPFIX Message.
The tester must check that an error was logged.
The tester must create another IPFIX Template and cause it to be
exported to the Collecting Process over SCTP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must cause a Template Withdrawal Message for the Template
to be sent to the Collecting Process over the same SCTP association,
and must ensure that the Template has been discarded by the
Collecting Process.
The tester must create Data Records conforming to the Template and
cause them to be exported to the Collecting Process over the same
SCTP association.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The tester must ensure that the Collecting Process discards the Data
Records and logs a warning.
The tester must cause the same Template to be exported to the same
Collecting Process over the same SCTP association.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must create Data Records conforming to the Template and
cause them to be exported to the Collecting Process over the same
SCTP association.
The tester must ensure that the Collecting Process correctly receives
and decodes the Data Records.
3.6.8.2. Using TCP Transport
Refer to Section 10.4.3 of [RFC5101] for the Collecting Process's TCP
Template management specifications.
The tester must create an IPFIX Template and cause it to be exported
to a Collecting Process over TCP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must cause the same Template to be exported to the same
Collecting Process over the same TCP connection, and must ensure that
the Collecting Process resets the TCP connection and discards the
IPFIX Message.
The tester must create an IPFIX Template and cause it to be exported
to the Collecting Process over TCP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must modify the Template contents while retaining the same
Template ID.
The tester must cause the modified Template to be exported to the
same Collecting Process over the same TCP connection, and must ensure
that the Collecting Process resets the TCP connection and discards
the IPFIX Message.
The tester must check that an error was logged.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The tester must create another IPFIX Template and cause it to be
exported to the Collecting Process over TCP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must cause a Template Withdrawal Message for the Template
to be sent to the Collecting Process over the same TCP connection,
and must ensure that the Template has been discarded by the
Collecting Process.
The tester must create Data Records conforming to the same Template
and cause them to be exported to the same Collecting Process over the
same TCP connection.
The tester must ensure that the Collecting Process discards the Data
Records and logs a warning.
The tester must cause the same Template to be exported to the same
Collecting Process over the same TCP connection.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must create Data Records conforming to the Template and
cause them to be exported to the same Collecting Process over the
same TCP connection.
The tester must ensure that the Collecting Process correctly receives
and decodes the Data Records.
3.6.8.3. Using UDP Transport
Refer to Sections 10.3.6 and 10.3.7 of [RFC5101] for the UDP Template
management specifications.
3.6.8.3.1. Re-Using the Same Template ID inside the Template Lifetime
The tester must create an IPFIX Template and cause it to be exported
to a Collecting Process over UDP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
Before the Template lifetime expires on the Collecting Process, the
tester must cause the same Template to be exported over the same UDP
connection to the same Collecting Process and must ensure that the
Collecting Process accepts the Template.
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RFC 5471 Guidelines for IPFIX Testing March 2009
The tester must create a different Template with the same ID and must
cause this to be exported to the same Collecting Process over the
same UDP connection before the original Template lifetime expires.
The tester must ensure that the Collecting Process does not reject
the new Template.
The tester must create Data Records conforming to the new Template
and cause them to be exported to the same Collecting Process over the
same UDP connection.
The tester must ensure that the Collecting Process correctly receives
and decodes the Data Records.
3.6.8.3.2. Re-Using the Same Template ID after the Template Lifetime
The tester must create an IPFIX Template and cause it to be exported
to a Collecting Process over UDP transport.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must allow the received Template lifetime to expire on the
Collecting Process.
The tester must create Data Records conforming to the Template and
cause them to be exported to the same Collecting Process over the
same UDP connection.
The tester must ensure that the Collecting Process discards the Data
Records.
The tester must check that the Collecting Process logs a warning.
The tester must cause the same Template to be exported to the same
Collecting Process over the same UDP connection.
The tester must ensure that the Template was correctly received and
decoded by the Collecting Process.
The tester must create Data Records conforming to the Template and
cause them to be exported to the same Collecting Process over the
same UDP connection.
The tester must ensure that the Collecting Process correctly receives
and decodes the Data Records.
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RFC 5471 Guidelines for IPFIX Testing March 20093.7. TLS Connectivity and Policy Selection
This section lists tests that verify connectivity over TLS and
Datagram Transport Layer Security (DTLS) and proper selection of TLS
policies as specified in the IPFIX Protocol. It specifically does
NOT purport to test the security of IPFIX Message transport over TLS
or DTLS, as evaluating the security of a transport session is really
a test of the TLS or DTLS implementation over which a given IPFIX
implementation runs, and as such is out of scope for this document.
Refer to Section 11 of [RFC5101] for the security specifications.
3.7.1. TLS Test Setup
Setting up for TLS connectivity and policy testing requires the
creation of appropriate X.509 certificates and private keys for a
test environment and the configuration of a DNS server to answer with
consistent information for the hosts used in the test.
The tester must configure the following certificates:
1. A Certificate Authority (CA) certificate and associated
private key for signing the following certificates.
2. One certificate and associated private key, with a CN (Common
Name) or subjectAltName extension of type dNSName containing
the fully qualified domain name of the host, signed by the CA
certificate in 1, for each IPFIX Exporting Process in the
test.
3. One certificate and associated private key, with a CN (common
name) or subjectAltName extension of type dNSName containing
the fully qualified domain name of the host, signed by the CA
certificate in 1, for each IPFIX Collecting Process in the
test.
The tester must configure consistent forward (A, AAAA) DNS records
for each host in the test on a DNS server used by the hosts for name
resolution. Note that there is no need to configure reverse (PTR)
DNS records for the hosts, as no part of the protocol uses reverse
lookups.
The tester must ensure that the Exporting Process and Collecting
Process are on different hosts.
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RFC 5471 Guidelines for IPFIX Testing March 20093.7.2. TLS over TCP Connectivity Test
The tester must set up certificates and DNS as in Section 3.7.1.
The tester must configure one Exporting Process and one Collecting
Process with their appropriate certificates to transfer IPFIX
Messages over TLS over TCP.
The tester must create an IPFIX Template and associated Data Record,
and cause them to be exported over the TCP connection.
The tester must ensure that a TCP connection and a TLS connection
were established, must ensure that data was exchanged, and must
ensure that the data received at the Collecting Process is correct.
3.7.3. DTLS over UDP Connectivity Test
The tester must set up certificates and DNS as in Section 3.7.1.
The tester must configure one Exporting Process and one Collecting
Process with their appropriate certificates to transfer IPFIX
Messages over DTLS over UDP.
The tester must create an IPFIX Template and associated Data Record,
and cause them to be exported over the UDP connection.
The tester must ensure that UDP packets were sent and a DTLS
connection was established, must ensure that data was exchanged, and
must ensure that the data received at the Collecting Process is
correct.
3.7.4. DTLS over PR-SCTP Connectivity Test
The tester must set up certificates and DNS as in Section 3.7.1.
The tester must configure one Exporting Process and one Collecting
Process with their appropriate certificates to transfer IPFIX
Messages over DTLS over the Partially Reliable-Stream Control
Transmission Protocol (PR-SCTP).
The tester must create an IPFIX Template and associated Data Record,
and cause them to be exported over the SCTP association.
The tester must ensure that an SCTP association and a DTLS connection
were established, must ensure that data was exchanged, and must
ensure that the data received at the Collecting Process is correct.
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RFC 5471 Guidelines for IPFIX Testing March 20093.7.5. TLS Bidirectional Authentication Policy Test
This is an optional test for Collecting Processes only; it requires
the modification of an Exporting Process to NOT present a
certificate.
The tester must modify an Exporting Process to NOT present a
certificate.
The tester must perform the connectivity tests in Sections 3.7.2,
3.7.3, and 3.7.4.
The tester must ensure that the Collecting Process rejects the TLS or
DTLS connection establishment.
3.7.6. Exporting Process Identity Mismatch TLS Policy Test
The tester must set up certificates and DNS as in Section 3.7.1.
The tester must use a certificate for the Exporting Process that does
NOT match the fully qualified domain name of the host on which the
Exporting Process runs.
The tester must Perform the connectivity tests in Sections 3.7.2,
3.7.3, and 3.7.4.
The tester must ensure that the Collecting Process rejects the TLS or
DTLS connection establishment.
3.7.7. Collecting Process Identity Mismatch TLS Policy Test
The tester must set up certificates and DNS as in Section 3.7.1.
The tester must use a certificate for the Collecting Process that
does NOT match the fully qualified domain name of the host on which
the Collecting Process runs.
The tester must perform the connectivity tests in Sections 3.7.2,
3.7.3, and 3.7.4.
The tester must ensure that the Exporting Process rejects the TLS or
DTLS connection establishment.
4. Security Considerations
This memo raises no security issues.
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